#!/usr/bin/env python## Interpret.py: this file is part of the GRS suite# Copyright (C) 2015 Anthony G. Basile## This program is free software: you can redistribute it and/or modify# it under the terms of the GNU General Public License as published by# the Free Software Foundation, either version 3 of the License, or# (at your option) any later version.## This program is distributed in the hope that it will be useful,# but WITHOUT ANY WARRANTY; without even the implied warranty of# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the# GNU General Public License for more details.## You should have received a copy of the GNU General Public License# along with this program. If not, see <http://www.gnu.org/licenses/>.importosimportreimportsignalimportsysimporttimefromgrs.ConstantsimportCONSTfromgrs.DaemonimportDaemonfromgrs.ISOItimportISOItfromgrs.LogimportLogfromgrs.KernelimportKernelfromgrs.MountDirectoriesimportMountDirectoriesfromgrs.PivotChrootimportPivotChrootfromgrs.PopulateimportPopulatefromgrs.RunScriptimportRunScriptfromgrs.SynchronizeimportSynchronizefromgrs.SeedimportSeedfromgrs.TarItimportTarItclassInterpret(Daemon):""" This is the main daemon class. """defrun(self):""" This overrides the empty Daemon run method and is started when .start() is executed. This first daemonizes the process and then runs this method. Note that the Daemon class does not set up any signal handles and expects that to be done in the subclass. """# First we set up some inner methods:defhandler(signum,frame):""" On SIGTERM, propagate the signal to all processes in the cgroup/subcgroup except yourself. If a process won't terminate nicely, then kill it. Finally unmount all the mounted filesystems. Hopefully this will work since there should be no more open files on those filesystems. """mypid=os.getpid()whileTrue:withopen(os.path.join(self.subcgroupdir,'tasks'),'r')as_file:lines=_file.readlines()iflen(lines)<=1:breakfor_pidinlines:pid=int(_pid.strip())ifmypid==pid:continuetry:foriinrange(10):os.kill(pid,signal.SIGTERM)time.sleep(0.2)whileTrue:os.kill(pid,signal.SIGKILL)time.sleep(0.2)exceptProcessLookupError:passtry:_md.umount_all()exceptNameError:passsys.exit(signum+128)defsignalexit():pid=os.getpid()whileTrue:os.kill(pid,signal.SIGTERM)time.sleep(2.0)defsemantic_action(_line,objs,n,execstr):""" Execute the directive """ifself.mock_run:_lo.log(_line)returntry:iflen(objs)<n:raiseException('Number of objs for verb incorrect.')exec(execstr)exceptExceptionase:_lo.log('Bad command: %s'%_line)_lo.log('Exception throw: %s'%e)_lo.log('SENDING SIGTERM to pid = %d\n'%pid)signalexit()defstampit(progress):""" Create an empty file to mark the progress through the build script. """open(progress,'w').close()# Register the signals to terminate the entire process cgroupsignal.signal(signal.SIGINT,handler)signal.signal(signal.SIGTERM,handler)# Grab all the GRS namespace variablesrepo_uri=CONST.repo_uris[self.run_number]stage_uri=CONST.stage_uris[self.run_number]name=CONST.names[self.run_number]libdir=CONST.libdirs[self.run_number]logfile=CONST.logfiles[self.run_number]tmpdir=CONST.tmpdirs[self.run_number]workdir=CONST.workdirs[self.run_number]package=CONST.packages[self.run_number]kernelroot=CONST.kernelroots[self.run_number]portage_configroot=CONST.portage_configroots[self.run_number]# Initialize all the classes that will run the directives from# the build script. Note that we expect these classes to just# initialize some variables but not do any work in their initializers._lo=Log(logfile)_sy=Synchronize(repo_uri,name,libdir,logfile)_se=Seed(stage_uri,tmpdir,portage_configroot,package,logfile)_md=MountDirectories(portage_configroot,package,logfile)_po=Populate(libdir,workdir,portage_configroot,logfile)_ru=RunScript(libdir,portage_configroot,logfile)_pc=PivotChroot(tmpdir,portage_configroot,logfile)_ke=Kernel(libdir,portage_configroot,kernelroot,package,logfile)_bi=TarIt(name,portage_configroot,logfile)_io=ISOIt(name,libdir,tmpdir,portage_configroot,logfile)# Just in case /var/tmp/grs doesn't already exist.os.makedirs(tmpdir,mode=0o755,exist_ok=True)# Rotate any prevously existing logs and make unmount any existing# bind mounts from a previous run that were not cleaned up._lo.rotate_logs()_md.umount_all()# Both sync() + seed() do not need build script directives.# sync() is done unconditionally for an update run.progress=os.path.join(tmpdir,'.completed_sync')ifnotos.path.exists(progress)orself.update_run:_sy.sync()stampit(progress)# seed() is never done for an update runprogress=os.path.join(tmpdir,'.completed_seed')ifnotos.path.exists(progress)andnotself.update_run:_se.seed()stampit(progress)# Read the build script and execute a line at a time.build_script=os.path.join(libdir,'build')withopen(build_script,'r')as_file:line_number=0medium_type=Nonefor_linein_file.readlines():# Get rid of whitespace padding immediately_line=_line.strip()# Increment the line number by one and create the name of the# file for the progress stamp.line_number+=1progress=os.path.join(tmpdir,'.completed_%02d'%line_number)# Do nothing for lines with initial # or blank lines. Create# a progress stamp only if we are not doing an update run.ifre.search(r'^(#).*$',_line)or_line==''or_line=='+':ifnotself.update_run:stampit(progress)continue# For a release run, execute every line of the build script.# For an update run, exexute only lines with a leading +.ignore_stamp=False_match=re.search(r'^(\+)(.*)$',_line)if_match:# There is a leading +, so remove it and ignore any progress# stamp if its an update run.ignore_stamp=self.update_run_line=_match.group(2)else:# There is no leading +, so skip if this is an update runifself.update_run:continue# Skip a line if the progres stamp exists, or ignore it# because its an update run.ifos.path.exists(progress)andnotignore_stamp:continue# This is pretty simple syntax. The first word on a line# is a verb. The remaining words are objcts.sentence=_line.split()verb=sentence[0]objs=sentence[1:]# This long concatenated if is where the semantics of the# build script are implemented. Note: 'hashit' can only come# after 'tarit' or 'isoit' so that it knows the medium_name# to hash, ie whether its a .tar.xz or a .isoifverb=='log':ifobjs[0]=='stamp':objs[0]='='*80semantic_action(_line,objs,1,'_lo.log(\'\'.join(objs))')elifverb=='mount':semantic_action(_line,objs,0,'_md.mount_all()')elifverb=='unmount':semantic_action(_line,objs,0,'_md.umount_all()')elifverb=='populate':semantic_action(_line,objs,1,'_po.populate(cycle=int(objs[0]))')elifverb=='runscript':semantic_action(_line,objs,1,'_ru.runscript(objs[0])')elifverb=='pivot':semantic_action(_line,objs,1,'_pc.pivot(objs[0], _md)')elifverb=='kernel':semantic_action(_line,objs,0,'_ke.kernel()')elifverb=='tarit':# 'tarit' can either be just a verb, or a 'verb obj' pair.iflen(objs):semantic_action(_line,objs,1,'_bi.tarit(objs[0])')else:semantic_action(_line,objs,0,'_bi.tarit()')medium_type='tarit'elifverb=='isoit':# 'isoit' can either be just a verb, or a 'verb obj' pair.iflen(objs):semantic_action(_line,objs,1,'_io.isoit(objs[1])')else:semantic_action(_line,objs,0,'_io.isoit()')medium_type='isoit'elifverb=='hashit':ifmedium_type=='tarit':semantic_action(_line,objs,0,'_bi.hashit()')elifmedium_type=='isoit':semantic_action(_line,objs,0,'_io.hashit()')else:raiseException('Unknown medium to hash.')else:_lo.log('Bad command: %s'%_line)_lo.log('Unknown verb: %s'%verb)_lo.log('SENDING SIGTERM to pid = %d\n'%pid)signalexit()stampit(progress)# Just in case the build script lacks a final unmount, if we# are done, then let's make sure we clean up after ourselves.try:_md.umount_all()exceptNameError:pass